Sociogenetic Responses to Ecological Variation in the Ant Myrmica punctiventris Are Context Dependent

• Published in: Behavioral ecology and sociobiology Vol. 49; no. 5; pp. 375 - 386
• Main Authors: DeHeer, Christopher J., Vicki L. Backus, Herbers, Joan M.
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer-Verlag 23.04.2001; Berlin Springer
• Subjects: Animal and plant ecology; Animal nesting; Animal, plant and microbial ecology; Animals; Ants; Autoecology; Biological and medical sciences; Formicidae; Fundamental and applied biological sciences. Psychology; Insect behavior; Insect colonies; Insect ecology; Insect genetics; Insect nests; Myrmica punctiventris; Population ecology; Protozoa. Invertebrata; Queen insects; Social insects; USA, New York; United States; North America; America; Availability; Formicidae; Nesting site; Intraspecific relation; Insecta; Resource; Animal society; Social insect; Formicoidea; Investigation method; Social interaction; Arthropoda; Microsatellite DNA; Social organization; Hymenoptera; Invertebrata; Aculeata; Field study
• DOI: 10.1007/s002650000309
• ISSN: 0340-5443

Models of social evolution predict a strong relationship between ecological factors and sociogenetic organization in social insects (e.g. queen number, nestmate relatedness and population structure). Despite a large body of coherent theory, empirical support for these predictions is weak. Here we report the results of an experiment that manipulated two ecological parameters, food and nestsite availability, thought to be important for a population of the forest ant Myrmica punctiventris. Earlier work had shown that the sociogenetic structure varies between two populations of this species, and an ecological experiment in one of the populations (in Vermont) revealed that food supplementation had the strongest effects on nestmate relatedness. We repeated the experiment in the second population (in New York) and obtained strikingly different results. We show that nestsite supplementation had the strongest effect in the New York population, and that adding both food and nestsites affected nestmate relatedness in a direction opposite to that reported from the Vermont study. These results show that the ecological context is critically important for understanding the determinants of colony structure in ants. Furthermore, comparison of our data with that of a previous study shows that social organization in New York is temporally unstable. Thus, not only do ecological factors strongly influence social organization, but their influence can vary over time. Our study underscores the need for detailed information on the natural history and ecology of social species.